Need help, Blew rear posi with 4.56 and 35's.

[midnitewarya]

Hey all,

Apparently a stock rear posi on a 1991 K5 10 Bolt won't run 35's and 4.56s for long. Mine lasted 12,000 miles and then I blew it to shreds accelerating in a corner. It looks like everything in the pumkin is gone. The posi carrier is in about 100 pieces and I'm missing teeth on my ring AND pinion. Has anyone else done this? Any recommendations during the rebuild? I don't know what else I could have possibly destroyed, and I need some help.

A testament to the K5, after banging out the shrapnel, I was able to put my K5 in 4wd and drive it home. The rear diff cover was gone and there was no carrier of any sort in the axle. Aside for some real bad gas mileage, I drove 60 miles home no problem with no rear end.

Any help would be great, there are so many options to choose from, and I don't want to buy anything that's just gonna do it again.

Al

 

[daleearnhardt01]

There was no carrier in your 10 bolt and you drove 60 miles? How did the axle shafts stay in?

 

[midnitewarya]

Just the center portion of the posi is blown out, the ends of it are still there, but they have moved close together.

 

[midnitewarya]

Dang, I wish I knew how to post pics...

 

[dhcomp]

Yah basically the consensus is that 35's are the max on a 10 bolt....and way tooo much if u have a heavy foot.

TIme to get a 14 bolt FF

 

[dyeager535]

My guess is it looked like this:

As you can imagine, yes it's happened before. The problem is that it's NOT posi, it's a gov-lock, and the carrier just can't handle the shock load of big tires.

I drove mine home as well, (granted, only a block or so) I was kind of amazed the c-clips didn't fall off nor did the carrier bearings come apart, even though they were starting to slip out of the caps. Who needs full floating axles? J/K

 

[MattK]

if you're going to rebuild the 10 bolt make sure you do it with an open carrier.

IMO i wouldn't drop another dime on a rear 10 bolt.

 

[89GMCSuburban]

That's what I did. 10 bolt blew up, replaced with open carrier and new gears. Did that till I got the 14.

What happened is you were accelerating (Hot doggin it?) on that corner, wheels started to slip, gov-loc engaged, torque split the carrier. Happens a lot.

 

[trailblazr81]

Ya about 2 years ago my old 12 bolt didnt like 35's powered by a 383!! I broke my ring gear and carrier in half and took a good chunk out of the pinion!! Had it hanging out of the huge hole in the aluminum cover. Even blew a hole I could stick my finger through in the top of the housing. Ended up getting another whole rear end out of the junk yard. Luckily it happened leaving a stop sign a block away from my house. Thing went BANG!! Locked up the rear n I slid over to the curb. So I locked it into 4 lo and dragged it home. Got another loud bang halfway to the house and then the rear would coast. After that I bought a detroit locker. A couple months ago I got a 73 K20 with 14 bolt FF.

 

[jwglover]

how about 14bolt SF ,,, 6 lug disc brakes, it does have 3.73,
got one,,, it was in a 88 blazer _originally out of a 90 something ct1500.
this way you wont have to buy new tires ans wheels,
clear out in topeka ks,,

 

[midnitewarya]

Sounds Good

In response to jwglover:

Sounds great, I've been looking for a 6 lug 14 bolt for awhile. Only problem would be is that I would still have 4.56 up front, so that means no wheelin for awhile. Just drop me an email ([email protected]) and we can talk about it.


Al